1. Field of the Invention
The present invention relates to the field of data processing. More specifically, the present invention relates to methods and systems associated with email service hosting and consumption.
2. Background Information
The popularity of Internet connectivity has contributed to the fast and persistent adoption of server applications in both the enterprise and the consumer space. The features and functionalities of a particular application are no longer confined to individual machines on which the application software is installed. Instead, these features can now be made available on the Internet or on the enterprise corporate network in an ongoing service model, accessible from any machines anywhere, anytime. Also, users do not have to keep up with the nuisance of software upgrades. Since new releases only have to be installed on the central server, users can immediately benefit from the feature upgrade via the Internet, without any of the complications of installation, configuration and system compatibility check. Some of the web-based applications that have become ubiquitous by now are email management and PIMs (Personal Information Management, including calendar, contacts and tasks).
However, such a convenience comes with a toll on bandwidth and storage cost, which are the primary cost drivers of server applications:
Bandwidth Cost
Since the processing power and database reside on the server, a high volume of data traffic is often created between server and client access points, and among servers themselves. To send bits from client A to client B, the supposedly straightforward data route from point A to point B now necessitates the intermediation of several servers in between, resulting in a significantly larger amount of traffic compared to a direct peer-to-peer connection.
As bandwidth is always subject to supply constraints due to its high capital cost and long lead time to deploy, ASPs and server applications have to strive hard for a way to reduce the data traffic while sustaining the same level of service to its customers.
Growth of Data Size
As server applications continue to upgrade their feature sets to include rich media formats (such as .JPG, .WAV and .MP3), the amount of data that needs to be transmitted and stored has grown significantly, to the point where the extra burden placed on bandwidth and storage has outpaced what can be viably offered by current-day technology. For instance, a textual email is typically only a few kilobytes in size; adding a 5-minute MP3-encoded song as an attachment can boost this size to about 5 megabytes, an increase of more than three orders of magnitude; video attachments add one more order of magnitude in size.
Storage Requirements
Storing copies of files for all subscribers on the server adds up to a hefty cost. In addition to directing and temporarily storing email before it reaches its final destination, some servers are also configured to keep backup copies of all email. For instance, the IMAP4 protocol keeps a copy of all received mail messages and attachments on the server unless instructed by the user to delete.
Such concentration of server storage model brings forth two problems:
First, there is a redundancy of storage beyond needs. For example, once an email is sent, the sender keeps the original copy of any attachments on his personal computer; the attachments also reside in the sent mail folder on his server. On the reception side, the receiver keeps a backup copy of the email and attachments on his mail server (which could be a operated by a different provider), and also downloads these to his desktop machine. Thus an attachment file meant for two parties now becomes populated on servers on both ends, exerting unnecessary burden on the storage needs of the intermediating servers. To wit, most web-based email services are currently only able to provide enough space to store one MP3-encoded song attachment per user mailbox; due to these size restrictions, users of these services cannot send video clips as email attachments at all
Second, multiple copies of the same document residing on both servers and client machines tend to cause confusion when changes are made. Data integrity has always been a difficult problem to tackle, especially in a world that promotes ubiquitous access to the same data. For example, when the receiver of an attachment makes certain changes and sends them back to the author via a web-based email system, the sender needs to upload the document again, no matter how small the change is; this cycles the new version of the document through the same storage duplication as the incoming route. Not only does this approach make it hard to keep track of changing data, but it also contributes to redundant storage of the same file over and over again, although each copy may be only marginally different from each other.
In order to save bandwidth and server space for data that cannot be handled otherwise, a huge opportunity exists to leverage the under-utilized storage space, processing power, and network bandwidth of the user machines themselves. This opportunity is based on a distributed computing model to assist certain server functions, and to allow server intermediation to be forgone as appropriate. Redundant storage of the same document can be minimized. This not only saves bandwidth and disk storage costs for the operators, but also enhances the performance of data transfer, and makes it easier to keep data distributed and synchronized at a much faster speed.